Orthopedic physicians are frequently challenged when performing arthroscopic surgery because of the limitations of the design and technology of the optical/video systems and instruments. The goal of arthroscopy is to perform minimally invasive surgery as an alternative to open surgery. Arthroscopy has proven to be safer, less painful and have a faster recovery time for patients when compared to open surgery. However, to duplicate the effectiveness of open surgery, which offers a three-dimensional perspective of the joint, a physician must adapt to a more challenging technique, using rigid scopes and a camera that transmits a video image onto a two-dimensional television or LCD monitor. Thus, the currently available conventional arthroscopic equipment poses some major challenges for physicians.
For example, conventional rod-lens arthroscopes are linear in design and a physician must steer this direct vector tool inside the joint in order to use the scope. These arthroscopes have an objective lens that is tilted in a fixed plane, e.g., 30, 45, or 70 degrees off the center line of the scope. This scope design forces the physician to use triangulation techniques with the scopes and instruments in order to operate on a target area in the joint. Considering the space constraints, the patient's anatomy, and the complexity of repair that may need to be performed, rigid arthroscopes do not easily allow 360 degrees of visualization inside the joint without switching to different portals or scope angles. This often makes it difficult for a physician to orient himself correctly, perform a proper diagnosis of anatomy and pathology, or visualize his instruments as they are being introduced into or used within the joint.
In addition, since conventional arthroscopes are linear in design, they are typically rigid and do not allow for any flexibility of movement around anatomical structures. However, human joint cavities are not composed of straight vectors and right-angled corners. Instead, the natural geometry inside human joints is a web of curved bones, condyles, and uneven articular surfaces held together by ligaments and tendons at various anatomical attachment points. Hence, rigid scopes and instruments limit the mobility and access of physicians into all areas of the joint, which affects a physician's ability to perform the best, or at least the most efficient, repair possible.
Other limitations of current optics/scopes and instruments include the fact that linear/direct-vector scopes and instruments are not able to reach all areas of the joint, especially when steering over or around anatomic structures. Rod-lens arthroscopes are also fragile and are easily damaged by reprocessing, handling and intra-operative use. They are also prone to fogging, scratched lenses and material build-up on the windows, all of which reduce image quality.
Another limitation of conventional scopes relates to the optical chain, which is composed of three separate components: the scope, the light cable, and the camera head. This design is cumbersome and inefficient for today's standards because all three components must be purchased separately, sterilized, and then assembled for surgery. If a scope with a different angle of view is needed, the surgery must be interrupted as one scope is detached from the light cord and camera head and is replaced with a greater/higher angled scope, as needed.
Further, conventional video/optical chains use redundant cables, one for the fiber optic light cable (for light transmission) and another for the camera cable. Excessive cables in the sterile field clutter workflow and operating room efficiency, as well as increase the risk of cable damage during daily use, cleaning/handling and sterilization.
Video resolution may be lost using a conventional rod-lens scope and camera head because the joint cavity must first be illuminated through a series of fiber optic bundles (light cable and the scope). Then the image is transmitted through the scope windows, rod lenses, and bulky couplers into the camera head (either 1-chip or 3-chip) before the image is finally sent electronically to the camera processor. If any one of the components in this optical chain is dirty, not working correctly, or slightly damaged, the resolution and image quality sent to the monitor or peripheral devices is compromised. Additionally, most rod-lens arthroscopes only allow approximately 250-300 horizontal lines of resolution to the camera head.
The scopes, light cables, and camera heads offered by most surgical companies are not durable enough for autoclave sterilization. Most medical facilities enjoy the time efficiency, cost savings, and safety of steam autoclaving. Companies that do not offer an autoclave compatible video/optical chain are not meeting the needs of the global orthopedic customer market. This is especially true in the largest arthroscopy markets such as the United States' ambulatory surgery center market, and the healthcare systems in Europe, Japan, and Australia, where government health regulations have eliminated liquid soaking methods as an acceptable form of equipment sterilization.
Accordingly, there exists a need for a videoarthroscope that overcomes the problems and limitations of the conventional arthroscopes previously discussed.